Ventilating system on an internal-combustion engine

Abstract

A ventilating system on an internal-combustion engine is described that has balancer shafts for the balancing of mass of the second degree, the balancer shafts are driven by a crankshaft via a toothed belt in a clutch housing into which fresh air is blown via an inlet opening for cooling purposes. For an improved direct cooling of the toothed belt, at least one air guiding duct is connected to the inlet opening. This air guiding duct is formed by ribs and has at least one outlet opening in the direct area of the toothed belt from which air blows out in a targeted manner onto the toothed belt.

What is claimed: 
     
       1. A ventilating system on an internal-combustion engine of the type having balancer shafts for a balancing of mass of the second degree are arranged at an engine crankcase with the end of the crankshaft located in a clutch housing, the balancer shafts being in driving connection with the crankshaft by means of a toothed belt, said ventilating system comprising: an inlet opening for the conveying of fresh air into the clutch housing, and   an air guiding duct means connecting to the inlet opening, and having at least one outlet opening in the direct area of the toothed belt for directing fresh air in a targeted manner out onto the toothed belt.   
     
     
       2. A ventilating system according to claim 1, wherein the air guiding duct means is formed by ribs joined to the clutch housing and extending to the toothed belt. 
     
     
       3. A ventilating system according to claim 2, wherein a fan is placed onto the crankshaft which conveys the fresh air through the air guiding duct means. 
     
     
       4. A ventilating system according to claim 2, wherein at least one of the balancer shafts is equipped with elements for the conveying of fresh air. 
     
     
       5. A ventilating system according to claim 1, wherein spoilers are arranged on both sides of the toothed belt, and wherein the fresh air is conveyed through the space formed by said spoilers. 
     
     
       6. A ventilating system according to claim 5, wherein a fan is placed onto the crankshaft which conveys the fresh air through the air guiding duct means. 
     
     
       7. A ventilating system according to claim 5, wherein at least one of the balancer shafts is equipped with elements for the conveying of fresh air. 
     
     
       8. A ventilating system according to claim 1, wherein the air guiding duct means is formed or configured as an air guiding tube that extends along the interior side of the toothed belt and has several outlet openings through which fresh air flows out in a targeted manner onto the interior side of the toothed belt. 
     
     
       9. A ventilating system according to claim 8, wherein a fan is placed onto the crankshaft which conveys the fresh air through the air guiding duct means. 
     
     
       10. A ventilating system according to claim 8, wherein at least one of the balancer shafts is equipped with elements for the conveying of fresh air. 
     
     
       11. A ventilating system according to claim 1, wherein a fan is placed onto the crankshaft which conveys the fresh air through the air guiding duct means. 
     
     
       12. A ventilating system according to claim 1, wherein at least one of the balancer shafts is equipped with elements for the conveying of fresh air.